History of the .45 ACP Cartridge

USA -(AmmoLand.com)- In U.S. military circles for over one-hundred years; from the onset of the Civil War all the way to today, there has been a tendency to prefer a large diameter bore, subsonic pistol cartridge if we are required to use a non-expanding bullet in the round.

While the old cap-and-ball 1860 Colt Army and 1873 Single Action Army used a .44” round ball, and a 255gr .454” flat-tipped conical lead bullet, respectively, neither projectile was designed to expand, and what little expansion occurred was because of their soft cast lead construction rather than by design.

The Army Ordnance folks around the beginning of the 20th Century had seen the failures of round-nosed, full-metal jacketed bullets in the British .303 rifles, and our own .30 U.S. Government (aka “.30-40 Krag”) in stopping a determined armed assailant.

As a result of numerous instances of the new .38 service pistols being ineffective the US Army was forced to hastily re-issue mothballed Single Action Amy .45 Colts. IMG : historicalfirearms.info

They reasoned that their .38 Long Colt Model 1892 revolvers had shown similar poor results, and that the re-issuance of the .45 SAA (Single Action Arm) to combat and eventually defeat the Philippine Moros apparently worked, that our military review board sought to adopt another large bore handgun. The British too paralleled this thought process and as early as the mid-1880s they had already started issuing some of the first .455 Webley revolvers as a result.

The advent of smokeless powder, its clean burning, and the copper jacketed bullet meant that Colonel John Thompson and Major Louis La Garde’s study of the effect of handgun bullets in 1904 suggested, via an observation of momentum transfer (motion of hung sides of beef, human cadavers), as well as some shooting tests on live cattle, offered a hypothesis that “calibers no less than .45” were the way to go.

. 45 ACP Cartridge

By the middle of the first decade of the 20th Century, Colt was into development along with the genius designer of most of their handguns, John Browning, of a .45 cal. Semi-automatic pistol. While the original development utilized a 200gr bullet at approximately 900 foot-seconds in 1906, subsequently the Ordnance Department desired a cartridge that approximated the old .45 Colt revolver cartridge in power, while being shorter in length to the substitute standard .45 S&W Schofield round.

Thus, the 230gr RNFMJ bullet and 850fps nominal speed template was created, and it found a home in our concurrently developed Colt Model 1911 pistol, the longest serving pistol of any military force to the best of my knowledge, some 75 years of official issue.

The . 45 ACP cartridge has a very slight taper, some 0.003” from case head rim to case mouth, so it can be considered a straight case for feeding purposes. The cartridge has changed only in the adoption of non-corrosive primers and different powder formulations in the mid-1950s, and it was known always as “Cartridge, Ball, M1911, Cal. 45” for its entire military service life.

In the civilian world however, it has remained as popular as ever. Due to the existence of new generation jacketed hollow point bullets, it still retains its terminal ballistic advantages of expansion and consistent penetration compared to other smaller bore diameter offerings. A recent detailed study indeed illustrated that the Federal HST 230gr standard pressure rounds offer 16” of penetration and consistent 0.85” of controlled expansion with no bullet fragmentation in an unofficial “FBI heavy clothing test” into simulated ballistic gelatin.

The .45 ACP operates at a very low 21,000 copper units of pressure, it has no supersonic crack, and is therefore nearly ideal for use with a suppressor.

One other thing that is not mentioned much is that its stopping power is achieved without superior “sectional density,” high pressure, or high velocity. It operates at a very low 21,000 copper units of pressure, it has no supersonic crack, and is therefore nearly ideal for use with a suppressor. The recoil, while “there,” is more a push than a quick snap, while controlled-pairs shooting aimed rapid-fire are pretty easy to do out to ten yards and can usually be within an inch of each other. I’ve done it, and I’m just not that great a shot.

Moreover, the . 45 ACP cartridge has long borne the brunt of technical development as a precision target shooting round as well as being a supremely controllable defense round. In both the original 230gr RNFMJ format for “hardball matches,” as well as reduced weight 185gr and 200g target matches, it remains one of the most accurate service pistol rounds extant. When a tuned 1911 style pistol is coupled with this ammo, it’s little surprise to me that retired USMC Gunnery Sergeant Brian Zins has now triumphed at the National Matches at Camp Perry, Ohio as overall champion a record twelve times from 2002 through 2013. His accomplishment will likely never be equaled. (He’s also a really nice guy whom I met at SHOT show in 2013).

Brian Zins Wins 11th NRA National Pistol Championship

To this day, agency elites such as LAPD SWAT, FBI HRT, and USMC SF still use the 1911 and its revered the . 45 ACP cartridge. It is an American Classic.